What was a major foreign policy failure during the Carter presidency?

A major foreign policy failure during the Carter presidency was the Iran Hostage Crisis, which began in November 1979 when Iranian revolutionaries seized the U.S. Embassy in Tehran and took 52 American diplomats and citizens hostage. The crisis lasted 444 days and significantly damaged U.S. international standing and Carter's reputation. Efforts to negotiate the hostages' release were unsuccessful, culminating in a failed rescue mission in April 1980. The crisis ultimately overshadowed Carter's presidency and contributed to his defeat in the 1980 election.